Do Marvel trilogies tell a complete story?

[Batgirl0202]

As an aside, I would also say that most "trilogies" in movies are similarly nothing of the sort. They are just a movie with two sequels, they weren't designed as a cohesive story told in three parts.

Definitely agree. I would also say that these "trilogies" existed for about as long as public interest remained high. The first movie was successful enough to warrant a sequel, and the sequel was successful enough to warrant a second sequel. If the franchise ended up being a trilogy, it probably had much to do with public reception of the second sequel...

Of course there are always exceptions, with LOTR being an obvious example...